Albert Einstein published his theory of relativity in 1915 that the speed of light in a vacuum is unaffected by the motion of all observers and that the laws of physics are the same for all observers not moving or accelerating.

The theory allowed scientists and researchers to predict black holes, and even the behavior of planets in orbit. The theory explains that when we try to measure how fast something is moving, that speed can only be determined in relation to another object’s speed.

Einstein also predicted that the light from one star can be bent by the gravity from another star, and this will help us find the mass of the star with bent light. This theory was proved, after more than a hundred years with the help of Hubble Telescope. It is hard to find stars with the perfect alignment that can create an Einstein ring, a circle of light formed by one star passing in front of another star from our vantage point.

With the help of our Sun, scientists were able to measure White dwarf Stein 2051B mass as 68% of that of our Sun.